The vxfsconvert utility converts an ext2 or ext3 file system to a Veritas File System with disk layout Version 9. The conversion must be done on a Linux system. Conversion of all ext2 and ext3 file system block sizes is supported.

The SF Admin guide for 6.0.2 also says it converts ext2 and ext3 (does not mention ext4) and there is nothing in the 6.0.3 release notes to say ext4 is supported.

In terms of migrating ext2 or ext3 with little downtime the man page says:

The vxfsconvert utility takes approximately 4 to 5 times longer than running file system-specific fsck on ext2.